Thermostatic valve mechanism



June 6, 1939. J, A CER@ 2,161,773'

THEaMosTATIc VALVE MECHANISM Filed oct. 1, 193e 2 sheets-sheet 1 INVENTOR JOSEPH` lA'. CERNY June 6, 1939. J; A, CERNY 2,161,773Av THERMOSTATIC VALVE MECHANISM Patented June 6, 1939 THERMOSTATIC VALVE MCHANISM Joseph A. Cerny, Cleveland, Ohio, assignor to William T. Bentley, Cleveland Heights, Ohio Appueaudn otobr'1,`19as, serial Na, 1113,56:

.s claims. (ci. 23e-4s) 'I'his invention relates to thermostatic snap action mechanism, such as is used vfor regulating the supply of fuel to a burnerfor heating purposes.

One object of the invention -is to provide improved thermostatic control mechanism which is of simple construction capable of manufacture` atI low cost, which is reliable in operation and capable of convenient adjustment. or regulation,

and which is not liable to get out of order in use.

A further object of theinvention is to provide improved thermostatic control mechanism of the snap action type which`is so constructed and arranged as to be capable of calibration to sub- 18 stantially any degree of sensitivenesswithin reasonable limits, in which the parts'are of symmetrical form and so arranged as to reduce fric-I tion and wear and also capable of assembly in relatively small compass so as'to reduce the over- 20 all size of the completeddevice. Y

A further object of the invention is to provide thermostatic control mechanism of the character described in which the parts 'are capable of construction 'and assembly in their working positions by very simple and convenient operations, and are of such formas to be substantially unaiected by the ordinary wear and tear towhich they are subjected in use and are consequently reliable in `operation over a long period of time. Further objects of the invention are in part obvious and in part will appear more in detail hereinafter. 1

In the drawings, Fig. 1 represents a longitudinal sectional elevation through one form of mechanism embodying theinvention; Fig. 2 is alsectional elevation on the line/2 2, Fig. 1;' Fig. 3 is a detail view, corresponding to Fig. 1, and iilus trating a modication; Fig. `4 is a detail sectional plan View, on thev line 4,-4, Fig. 1, 'illustrating o the movable carriage; Fig. 5 is a detail perspective view of that member of the carriage tovwhich the main spring is attached Fig. 6 is a view corresponding to Fig. 1 and illustrating another embodiment of the invention; Fig. 7 is a Asectional elevation on the line 1-1, Fig. 6; Fig. 8 is a detail perspective view of the valve actuating lever; Fig. 9 is a similar vi'ew of the main lever; and'Fig. 10 is a perspective view-of the movable carriage shown in Fig. -6.

5o While the invention is capable of use for any purpose such as for operating electric switches or wherethe 'flow oi' fuel for heating purposes is to be controlled, such as industrial furnaces or boilers, space vheating apparatus,fsuch as household or other devices,- one common use 'of the mechanism is for controlling or regulating the temperature of the heated water for a domestic hot water supply system in whicli the water is heated by gas.v Such a device is illustrated in the drawings. I indicates the part 5 whose motion or position is to be controlled. Where the control mechanism is used for electric circuits this part will be connected to a suitable electric switch, but in the drawings part 1 is shown as a gas valve. 'Ihe control mechanism m includes a suitablecasing or body member I, usually a bronze casting cored out to provide an elongated chamber 2 provided at one end with a threaded opening 3 through which gas ows to the heatingfbumer,` said chamber being sepil arated from a gas supply chamber l in a lateral extension of the housing by a valve seat 5. The chamber 4 communicates with a threaded opening 6 to which is connected thegas supply pipe (not shown). lCooperating with the seat 5, and zo therefore controlling the ow oi gas from the inlet opening 6 to the outlet opening 3 is a suitable valve device, such as the valve Vmember l lightly held to its seat by a compression spring 8 within the sleeverof a cap 9. The stem I0 of the 'valve u slides in an end head Il and surrounding said valve is a filter-screen I2.

Cap 9 with its attached parts, including the valve, its stem 'and spring, and head I I Aand screen I2 may be unscrewed and removed asa unit from ,o the housing for repair or replacement and to aiord access to the valve seat when necessary.

vAlso, whilethe chamber 21s usually contained 'wholly within the housing I, it is open overgits entire length on one face where it is closed by 35,.

a removable cover I3 of plate form. All the parts of the operating mechanismmay be inserted into 'or removed from chamber 2 when this plate-like housing and within which is contained a relatively non-expansible member, such as the steel or porcelain rod I6. The inner end of said'rod vextends into' chamber 2 opposite valve 1 and its 50 outer end is threaded into a plug I6 threaded into tube I l, .This plug may be adjusted back and.forth along. its/threads for a lproper initial setting of the mechanism, as is usual, Also, the rod I5 is provided with operating means, such as lll an arm I1 attached to it by a set screw I8 and.

accessible from the outside of the casing for manipulation to vary the temperatureto which the thermostatic mechanism is responsive. 'Ihe 5 casing. I is threaded at I9 for attachment to a fitting on the wall .f a water container, such as a domestic hot water tank, with the thermostatic elements I4, I5 extending into the water and sensitive to the temperature thereof.

The operating mechanism connecting the thermostatic elements for actuation of. valve 1 is as follows: l

indicates a main lever and 2| a secondary or valve actuating lever.

and stamped or pressed to proper shape and form and therefore capable of manufacture at low cost. v

The main'lever 20 at one end is bent out of lthe plane of its body portion to form 'an offset 20 end portion v22 of substantial width .and arranged for pivotal connection to the body or casing I. This may be a pin pivot but is usually a knifee'dge pivot, the knife edge 'beinglformed by slightly bending the extreme end portion of the metal out of the plane of theoilset 2 2, as indicated at'23, so that one of the transverse .edges of the metal where it is sheared 'or .cut oif square at its end lever-28 is formed in suitable manner to engage a movable carriage or motion transmitting memv40 ber, two forms'of which are shown in the drawings. y

In Fig. 1 the carriage comprises a body meniber 25 ofv plate-like form provided -with an elon-P gated slot 26 and at each end shaped to'form pockets or cups 25a, such as by bending the metal into channel form. Extending fairly loosely through the slot 28 is a plate-like member 21 provided with shoulders 28 abutting the under surface of plate 25 beyond the ends of slot 28, the upper portion of plate 21 being provided with an opening 28 to receive one end oi' a strong coiled tension spring 38. The lower portion of member 21-is bentlaterally to form a tongue. 8| upon which is sleeved one end of a compression u spring 82, the opposite end of which abutsvthe wall of the casing.

In each of the pockets 25a'are one or more (two being shown) of anti-friction members such as balls, preferably held separated from a0 each otherin-any suitable manner, such as by teats 3l punched upwardly from the bottoms oi' the pockets 254. The haus n rou along smooth or ilnished-undervsurfaces 85 ot solid abutments 88, 88a, separated from each other but each cast l mtegrslly'wicn the metal of the' body l.' The upper arm of plate 21, ofcourse, lies and travels between the'ltwo abutments I8, 38a. Spring 88 extends along one face of the main lever 28 and lies between the arms 2| a of the valve actuatingv 7o lever 2i, which' is generallyof vU-form as shown in Fig. 8, but said lever is provided at its head .end with a curved extension 21,l the arch 'of which f .lies directly opposite `the center of valve 1 and the end of which lies opposite the onset portion 75 22 of the main lever, as shown in Illg. 1. Said Both of theselevers 15 are preferably made of pressed sheet metal cut y spring 32.

the edge ofthe plate 25.

extension is also providedwith suitable means,

such as the opening 38 for attachment to it of at 2Ib, so that one edge of the metal at the end A10 of veach arm forms a knife edge presented endwise from the lever as a Whole, the knife edges on the two lever arms resting in seats or bearings 39 in the upper faces' of the abutments 36, 36a.

With this arrangement the bottom surfaces 35 and upper surfaces '39 of abutments 35, 36'a and, the bearing surfaces or seats on the abutments 24, 24a, may be readily formed or finished by a single broachingoperation with.a.single tool,` as will be readily apparent. y

Main lever 201is made eiective upon the movable carriage to which the spring 30 is connected, by forming and locating the free end of the main lever in suitable manner to abut the carriage on that face of its plate 21 opposite to the As shown in Figs. 1 and 9,` the -lower or free end of the main lever 2U is bifurcated and bent out of its plane to form two iingers 20a, straddling that turn of the spring 30 which is connected to the carriage and abutting the up wardly extending portion of plate 21 of the carriage. Fig. 3 illustrates 'another arrangement in which the free end of the-main lever 2Il Iis unbent or plain and extends down alongsideof and abuts The operation is as follows: Fig. 1 shows the parts in their positions when thedevice beinghea'ted is up to or abovev the desired temperature. In other words, .no heat is demanded. Therefore valve -1 is closed and lever 2I is in its oif position with its free endabutting the main lever 20. A line drawn from the Vpoint of connection of spring 30 to plate 21 to the connection of the opposite end vof said spring to lever-2| lies at the right, in 1 ',"of the knife-edge pivot of lever 2|. The movable carriage is lightly pressed by the spring 32 against the lever 28, either against the end-of its iingers 20a in Fig. 1, or by pressure of the edge of plate 25 against the ilat surface oi' lever 28 in Fig. 3.

. As the device to be heated cools, such as by cool-A to the left in Fig. 1 to fully open position. This operation, of course, compresses spring 82. It

also supplies gas to the burner and "when the 'temperature of the 'water rises .sufilciently a. con 65' trary eil'ect occurs, tube Il expanding and cans# ing movement of rodv I5 to the right, with corresponding motion of lever 20, accompanied by return movement of the 'movable carriage as the result of the compression of spring 32. Again, when the dead center is passed, lever 2I -is snapped over to the right or to the position shown .in

Fig. 1,'thereby permitting the valve to close.

Lever 2 8 is subjected to two forces, to wit, to the pressure of rod I5 in one direction and to the 1 'loA pressure upon'it of the'movable carriage as the result of the compression of spring 32. In the form shown in Fig. 3 the pressure of the lever4 upon the movable carriage is applied in lsubstantially the'plane of the surfaces 35 along which the balls roll with 4substantially no tendency to turn or cock the carriage from its normal position. In both forms lever 2| is subjected to the eifect of butv a single spring, extending longitudinally equal pressure of both of its legsupon the, seats in which they pivot and with no tendency toward twisting or askew movement. The balls or antifriction members 33, of course, reduce friction of the moving carriage along the surfaces on 'which it travels.

This device may be readily calibrated to a high degree of sensitivity..` In these instruments sensitivity depends to alarge degree upon the closeness movable carriage to the line of the pivotal mounting of lever 2| in the casing, or in other words, to the line of the knife-edge pivot of said lever. The nearer one is tothe other the more sensitive is the device. Sensitivity may be readily inthe lever movement as between the amount of motion of rod I and the amount of motion of the carriage produced thereby.

Figs. 6 and 7y illustrate a modification differing only from the form shown in Fig. 1 as to the form of the movable carriage.' The movahlefcarriage in this arrangement is a single member of plateA form, shown in detail in Fig. 10. It comprises a body portion 40, the lower portion of which is pin 42 mounted in openings 43 in solid bosses I of the body I. The upper portion of plate 40 is punched out to forma tongue 44, forming a perch for the compression spring 32 and' corresponding punching out said tongue provides an opening for attachmentvof the spring 30, and just as in Fig. 1 the upper end of plate 40 is bent slightly iaterauif, as at 41, to present a. knife edge to the turn of spring passed through said opening.

The operation of this device is the same as that of the form before described, differing only in that the main lever 20 here produces swinging motion in one direction of the carriage around its pin pivot, its swing-ing motion in the opposite direction being produced by the spring 32. Sensitivity is readily varied, such as being increased, Iby more or less filing or broaching out the openings 43 or those in earsy 4| vwhich receive the pivot -pin 42, such as by filing out said openings `43 above the pin, as indicated bythe dotted lines-at 46, thereby raising'the pivot pin in Fig. 7 and bringing the point of connection of spring 30to the` movable carriage closer to the knife-edge pivot of lever 2|.

creasing the sloppiness of the t of the pivot pin in its opening. l Y

With each' of the levers 20 and 2|, where they are formed for connection vto any other part, 75 such as where they have a knife-edge bearing in along its center and tending to hold it rmly with creased,'if the device is too insensitive, by taking' affecting only the amount of multiplicationof to the tongue 3|, Fig. 1. The slot 45 formed by In other words, sensitivity is here increased by inthe like.

of the pointof connection of spring 30 with the bent to form two ears 4| pierced to receive a pivot ner described, in the very act of originally formthe casing or where arranged for connection to an' end of spring 30 or where lever 20 is bent to form feet 20a engaging the carriage, it will be observed that the metal of the lever is shaped, by cutting or otherwise, to form a transversely 5 extending square' formed edge portion, the metal adjacent which edge portion is bent diagonally out of the gener-al plane of the sheet to present two sharp edges, one in the direction of the plane of the sheet as a whole and the other normal to said plane, one of which edges may b e utilized as a knife edge for its connection to another part. This isa very simple and convenient method Aof forming a knife edge suitable for use in the maning or shaping the blank, without any special operative steps such, as grinding, sharpening or It will also be observed that the movable carriage, consisting of the two sheet metal parts 25, 21 in Fig. 1, and 4|) in Fig. 6, not only serves as a support for one end of the main spring 30, but also as a simple motion transmitting member, receiving motion from the main lever and transmitting it to the spring for causing snap action of lever 2|.

In all forms of the invention, when the cover I3 is removed the operating parts of the mechanism may be readily introduced into the cavity or chamber of the casing and there assembledl and adjusted to proper operating condition., Access to said parts, when in s itu, is convenient for purposes of adjustment, replacement, repair or cleaning.

Other` advantages of the invention will be `What I claim is: A L

1. Thermostatic control mechanism, .comprising a chambered casingpro'vided with oppositely disposed spaced abutments, a generally u -shaped actuating lever provided with an operating'head and having the free ends of its armspivotally mounted upon one side of said abutments, a mo tion transmitting member mounted in the casing on the other side of said abutments and having a partA arrangedto travel back and forth between them, a tension spring lying between said arms and extending from said head to a point beyond the pivotal axis of the lever and there connected to the said part of said motion transmitting member, yieldable means for moving Asaid motion transmitting member in onedirection, an operating lever lying alongside the actuating lever,

said -operating lever at one end moving between said abutments and engaging 'the motion transmitting member and at theother end being pivotally mounted in the casing, and thermostatic means operatively effective upon said operating lever.

2. Thermostatic control mechanism, comprising a chambered casing providedwith oppositely disposed spaced abutments, a generally U-shaped actuating lever provided with an operating head andhaving the .free ends of its arms pivotally mounted upon one side of said abutments, a 05 'ing said motion transmitting memberl in one direction, and thermostatic means for moving it in 75 the opposite direction,l saidA motion transmitting memberv being formed of pressed sheet metal and shaped to provide pockets, and anti-friction members lying in said pockets and travelling along said abutments.`

3, Thermostatic control mechanism, comprisying a chambered casing provided with oppositely disposed spaced abutments, a generally U-shaped actuating lever provided with an operating head and having the free ends of its arms pivotally mounted upon one side of said abutments, a motion transmitting member mounted 'in the vcasing on the other side of said abutments and metal sheet to form a perch for said pressure spring, said motion transmitting member being also formed to provide pockets, and antifriction members lying in Saidpockets and travelling along said abutments.

4. Thermostatic control mechanism, .comprising a chambered casing provided with oppositely disposed spaced abutments, a generally U-shaped vactuating lever provided with an operating head and having the free ends of its armspivotally mounted upon one side oi said abutments, a mo tion transmitting member pivotally mounted in the casing on the other side of vsaid abutments andhaving a part arranged to travel back and forth between them, a tension spring lying between said arms and extending from said head to a point beyond the pivotal axis of the leverand there'connected to the said part ofv said motion transmitting member, yieldable means for moving said motion transmitting member in one direction, and thermostatic means for moving it in the opposite direction.

ademasV 5. Thermostatic valvemechanism, comprising a hollow casing provided with supply and discharge chambers separated by a valvel seat, a valve cooperating with said seat, thermostatic 'operating means extending' into one of said chambers, a main lever pivoted in one end of said chamber near said means and actuated thereby and extending toward the other end of said chamber, a valve actuating lever pivoted in the casing near the other end of said chamber and lying beside the main lever. a motion transmitting member pivotally mounted-in said casing beyond the valve actuating lever and having a spring receiving portion located beyond its pivot, a tension spring extending from said portion to a remote point on the valve actuating lever, a pressure spring tending to move said motion transmitting member in one direction, and said main lever engaging said motion transmitting member to move it in the opposite'direction.

' 6. Multiple leverage thermostatic control mechanism of the character described, comprising a chambered casing open at one side, two pairs of spaced abutments, one pair near each end of said casing and integral with itswalls and having lever pivot supporting surfaces extending'normal to the open side of said casing, enablingv all of said surfaces to be machined accurately in one operation, main and secondary levers in said casing extending in opposite directions and lying generally parallel with each other, said levers having knife edge pivots bearing respectively one on each pair of said abut? ments, a motion transmitting member bearing directly on the casing and mounted for movej ment to opposite sides of said secondary lever pivot and adapted for operation by said main lever, yielding means acting on said motlontransmitting member to maintain it in contact withsaid main lever, a tension spring extending from the vfree end'of said secondary lever t'o said motion transmitting member, thermostatic means acting on said main leven-and an actu- Y ated device operated by said secondary lever.

JOSEPH A. -CERNY 

